/Engine/Source/Runtime/RHI/Public/RHIResources.h
Shaders that can be explicitly invoked from RayGen shaders by their Shader Binding Table (SBT) index. SetRayTracingCallableShader() command must be used to fill SBT slots before a shader can be called.
void SetCallableTable ( const [TArrayView](API\Runtime\Core\Containers\TArrayView)< [FRHIRayTracingShader](API\Runtime\RHI\FRHIRayTracingShader) * > & InCallableShaders, uint64 Hash )